To disable the Dashboard on a Mac running Snow Leopard just execute the following line in a command window.
defaults write com.apple.dashboard mcx-disabled -boolean YES && killall Dock
and to re-enable it just dexecute this line in a command window.
defaults write com.apple.dashboard mcx-disabled -boolean NO && killall Dock
Dashboard is a resource hog, so if like me you don't use it you can now get it out of your way. Credit goes to jonathans blog for the execution code.
Ramblings of an old computer engineer/developer 